PURPOSE: To make possible easily a microminiaturization of a semiconductor device by a method wherein the connection between a photoelectric conversion element chip and insulating substrates is conducted by a face down bonding and the insulating substrates are formed into forms corresponding to the bump parts of the element chip.

CONSTITUTION: Bumps 2 for electrode connection use are arranged on both sides of a photoelectric conversion part of a photoelectric conversion element chip 1, such as phototransistor, an LED or the like. Insulating substrates 3 consisting of alumina, glass, a glass fiber reinforced epoxy resin or the like are formed into forms corresponding to the arrangement parts of the bumps 2 of the chip 1, pads for face down bonding use are so provided as to correspond to the bumps 2 of the chip 1 and moreover, external connecting leads 4 are respectively provided on the arrangement surfaces of the pads. The chip 1 is bonded to the substrates 3 by a face down bonding. A protective glass or an optical filter 5 is stuck on the surface of the chip 1 with a transparent resin 6 dripped on the surface of the chip 1.